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关键词： Lunar regolith simulants   Particle morphology   Shear strength   X-ray computed tomography  

摘要： Reliable assessment of lunar surface excavation, mobility, and in-situ resource utilization (ISRU) relies on mechanical properties of lunar regolith simulants, which differ substantially in particle morphology and gradation. However, systematic comparative studies on the morphology-mechanical behavior of commonly used simulants remain limited. This study presents a comparative investigation of three representative lunar regolith simulants, LHS-1, LMS-1, and LSP-2, using high-resolution micro-computed tomography (μCT) reconstruction and laboratory direct shear tests. Trainable Weka Segmentation (TWS) and level-set segmentation techniques were used to reconstruct the three-dimensional geometries of the particles, and multiscale shape descriptors were employed to quantify particle morphology. Principal component analysis and Mahalanobis distance evaluation revealed partially overlapping but statistically distinguishable morphological regions among the three simulants. The volume-weighted particle size distribution derived from the reconstructed particle reproduced the relative grading trend obtained from laboratory tests. Direct shear tests were conducted under normal stresses of 24, 48, and 96 kPa, with additional replicate tests used to assess repeatability and uncertainty. The Mohr-Coulomb analysis shows that LSP-2 exhibits the highest internal friction angle, followed by LMS-1 and LHS-1. Semi-quantitative analysis further indicates that the observed differences in shear strength are more reasonably interpreted when particle morphology and gradation are considered together, rather than by morphology alone. These results provide experimental support for numerical modeling and engineering design in future lunar surface operations.

关键词： Sleep stages   Glycemic variability   Type 1 diabetes   Pediatrics   Home sleep test  

摘要： Type 1 diabetes (T1D) may disrupt sleep through several mechanisms, including glycemic variability (GV). Few studies have examined nightly GV and its association with sleep architecture. We examined associations between nocturnal GV and sleep architecture in children and adolescents with T1D during the first 4 h of sleep, when stage N3 is most prominent.

关键词： Alzheimer's disease targets   Cadmium(II) complex   DFT   Dielectric relaxation   In silico studies   Molecular docking  

摘要： A novel cadmium(II) complex, [CdCl₃(HAEP)H₂O]·H₂O (HAEP = 1-(2-aminoethyl)piperazinium), was synthesized and characterized. Single-crystal X-ray diffraction reveals a slightly distorted octahedral geometry around the Cd(II) center, stabilized by a three-dimensional hydrogen-bonding network. DFT calculations indicate high electronic stability and charge-transfer potential. Molecular docking suggests moderate binding affinity to Alzheimer's-related enzymes (AChE, BChE, GR). Impedance spectroscopy reveals non-Debye dielectric relaxation and thermally activated localized conduction regimes associated with the heterogeneous hydrogen-bonded framework formed by protonated HAEP cations, chloride ligands, and coordinated/lattice water molecules. The combined structural, electronic, and in silico analyses highlight the complex's potential in coordination chemistry and bioinorganic applications.

关键词： Coconut water   Ergogenic   Radical scavenging   Multivariate data analysis   Metabolites  

摘要： The lyophilisation process helps to eliminate water,while retaining the bioactive compounds,and keeping co-conut water(CW)in a more suitable form for commercialisation purposes.However,little is known about the difference between the biological and chemical profiles in the lyophilised form of CW.Moreover,the variances across key Malaysian cultivars make it difficult to find high-value bioactive compounds.Lack of comparable chemical and functional data hinders the development of lyophilised coconut water(LCW)as a standardised,commercially viable nutraceutical and functional food ingredient.Thus,this research aimed to characterise metabolite differences and volatile compounds in the LCW from four popular coconut cultivars in Malaysia.The metabolites were detected using proton nuclear magnetic resonance(^(1)H NMR)combined with multivariate data analysis(MVDA)to correlate with their functional properties.The findings indicated that Malayan Yellow Dwarf(MYD)exhibited the highest levels of radical scavenging activities and in vitro anti-aging properties.The partial least squares(PLS)biplot revealed the presence of potent metabolites in MYD,such as epicatechin,valine,methionine,ascorbic acid,glycine,and catechin,which showed the highest correlation with the antioxidant and anti-aging activities.The characterisation results using HS-SPME-GC-MS showed that the volatile compounds in the LCW were grouped into esters,alkanes,alcohols,ketones,aldehydes,isocyanate,carboxylic acids,and phenols.To summarise,it can be inferred that LCW from the MYD cultivar has the potential to serve as a valuable natural ergogenic ingredient,with free radical scavenging and in vitro anti-aging properties,which holds promise for future advancements in the preparation of health product ingredients.

关键词： Nonlocal ∂̅ formalism   Green’s function   Fourier transformation   Generalized nonlinear wave equation  

摘要： A generalized (2+1)-dimensional nonlinear wave equation is investigated within the framework of $\bar{\partial }$-dressing method. By complexifying the temporal and spatial variables, a (4+2)-dimensional extension of this equation is derived. Through the introduction of two independent variables, the higher-dimensional equation is reduced to a generalized (3+1)-dimensional form. Based on this formulation, the $\bar{\partial }$-dressing method is employed to construct solutions. The results provide an effective approach for studying higher-dimensional nonlinear wave equations and further demonstrate the applicability of the $\bar{\partial }$-formalism in multidimensional integrable systems.

关键词： 1/f noise suppression   Differential measurement system   Dual-channel thermistor correlation coefficient   Temperature stability   TianQin satellite  

摘要： The TianQin mission is designed to detect space gravitational waves in the ultra-low-frequency (ULF) band, ranging from 10⁻⁴ Hz to 1 Hz, through the deployment of three satellites into geocentric orbit. During in-orbit operation, the satellite's laser interferometric system encounters a significant challenge: the excessive 1/f noise from thermistors in the temperature measurement system compromises the precise measurement of temperature fluctuations at the interferometer. This study presents a dual-channel differential measurement system, integrating a three-layer noise isolation structure into the second channel. The simulations demonstrate the effectiveness and feasibility of the proposed system. For the first time, a correlation coefficient model for dual-channel thermistors is developed, the key mechanisms governing the dual-channel thermistor correlation coefficient are elucidated, facilitating the suppression of thermistor 1/f noise in the ULF range within the temperature measurement system and enabling precise characterization of temperature noise in the onboard laser interferometric system. Finally, the proposed dual-channel differential method structure and model undergo simulation and optimization analysis, the results show that for the Betatherm 10K3A1A NTC thermistor at a reference temperature of 298.15 K, the dual-channel thermistor correlation coefficient reaches a maximum value of 0.9995. The maximum residual 1/f noise after differential processing is 56.11 μΩ·Hz^-0.5, compared to the single thermistor's maximum 1/f noise level of 1643 μΩ·Hz^-0.5, resulting in a noise suppression rate of 96.59%. This method is anticipated to improve the temperature stability of the laser interferometric system aboard the TianQin satellite.

关键词： Hemolytic anemia   Niacin   Vitamin B3   Ferroptosis   Apoptosis   Oxidative stress   DNA damage  

摘要：

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  Niacin ameliorates phenyl hydrazine-induced hemolytic anemia.
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  Niacin showed antioxidant, antiferroptosis properties.
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  Niacin attenuates hemolytic anemia by modulating Nrf2/HO-1/GPX4.

关键词： Alveolar bone   Bite force   Bone remodeling   Parathyroid hormone   Teriparatide  

摘要： Parathyroid hormone (PTH) is a key regulator of calcium homeostasis and bone remodeling. While intermittent PTH (1–34) (teriparatide) is an established treatment for osteoporosis, its effects on alveolar bone regeneration remain unclear. This study evaluated intermittent PTH (1–34) impact on the microstructure and remodeling of canine maxillary alveolar bone under physiological masticatory force.

关键词： DFT   Dual fluorescence   ESIPT   Hydrogen bonds   Molecular structure   Tautomerism  

摘要： 3,5-Bis(2-hydroxyphenyl)-1H-1,2,4-triazole (bis-HPTA) undergoes a self-assisted proton transfer trigged proton transfer (PTTPT) in the excited state. The effect of replacement of triazole ring with oxadiazole was investigated by synthesizing 2,2′-(1,2,4-oxadiazole-3,5-diyl)diphenol (HPOD) and its methoxy derivative 2-(3-(2-methoxyphenyl)-1,2,4-oxadiazol-5-yl)phenol (MPOD). Density functional theory (DFT) and time dependent DFT calculations were also done to validate the experimental results. Single crystal analysis revealed the planar structure of HPOD and presence of hydrogen bonds between the proton donor and proton acceptor in both the units, (labeled as α- and β-rings). The hydrogen bonded oxadiazole nitrogen of α-ring is attached to the carbon atoms and that of β-ring is attached to oxygen atom and carbon atom. Despite the existence of intramolecular hydrogen bonds in both units, excited state intramolecular proton transfer (ESIPT) occurs in the α-ring (ESIPT-I) only, and no ESIPT occurs in the β-ring (ESIPT-II). In nonpolar solvent, cyclohexane, only tautomer emission is observed, whereas in other investigated solvents, HPOD emits dual emission, normal and tautomer emission. In solvents such as dimethylformamide and methanol, an additional anion is also detected. Time resolved and theoretical studies also supported these observations. The methoxy derivative also undergoes ESIPT. However, the breaking of β-ring (by replacing the hydroxy with a methoxy group), reduced the ESIPT along α-ring also. Theoretically simulated vibrational spectra also suggest that the proton transfer is favoured in the α-ring of HPOD rather than β-ring. In conclusion the substitution of more electronegative oxygen decreased the tendency of ESIPT in HPOD.

关键词： Chronic obstructive pulmonary disease   Hypoxia-inducible factor-1α   Hypoxia   Inflammation   Airway remodeling   Natural compounds  

摘要： Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disorder defined primarily by persistent airflow limitation. Its pathogenesis involves multiple interrelated mechanisms, including hypoxia, inflammation, oxidative stress, airway remodeling, and pulmonary vascular remodeling. Hypoxia-inducible factor-1α (HIF-1α), the oxygen-sensitive functional subunit of the HIF-1 transcription factor complex, is stabilized under hypoxic conditions and mediates cellular adaptation to low-oxygen microenvironments by regulating glycolysis, angiogenesis, inflammatory responses, and metabolic reprogramming. Accumulating evidence indicates that HIF-1α can also be activated by non-hypoxic stimuli, including inflammatory cytokines, oxidative stress, cigarette smoke exposure, and several oxygen-independent signaling pathways. These findings support its role as a central molecular hub linking hypoxia, chronic inflammation, and metabolic dysregulation. In COPD, HIF-1α may contribute to disease onset and progression, as well as to COPD-related complications, by regulating airway inflammation, mucus hypersecretion, airway and pulmonary vascular remodeling, cellular senescence and apoptosis, and selected extrapulmonary manifestations. Several traditional Chinese medicine formulas and natural compounds have been reported to alleviate COPD-related pathological processes, partly through modulation of HIF-1α and its downstream signaling pathways. However, current evidence is derived mainly from preclinical studies or small clinical studies of limited methodological quality. Moreover, rigorous validation of HIF-1α-dependent mechanisms and high-quality randomized controlled trials remain lacking. This review summarizes the role of HIF-1α in the pathogenesis of COPD and its related complications. It also discusses recent advances in traditional Chinese medicine formulas and natural compounds that target HIF-1α, with the aim of providing a mechanistic basis for future COPD research